By introducing a mobility anchor point (MAP), hierarchical mobile IPv6 (HMIPv6) reduces the binding update signaling cost associated with mobile IPv6, but there still exist deficiencies. For instance, a mobile node (M...By introducing a mobility anchor point (MAP), hierarchical mobile IPv6 (HMIPv6) reduces the binding update signaling cost associated with mobile IPv6, but there still exist deficiencies. For instance, a mobile node (MN) needs to orderly accomplish two binding updates with the MAP and home agent (HA) when the MN performs inter-MAP mobility. This results in a high signaling cost, thus affecting network performance. To reduce the inter-MAP binding update cost of idle MN in HMIPv6, an optimization scheme based on pointer forwarding with a threshold is proposed. The scheme can reduces the binding update cost of idle MN by using the binding update between MAP to replace several home binding updates. The signaling cost difference is derived by analyzing the cost of the basic scheme and the optimization scheme between two successive sessions. Simulation results show that, the optimization scheme can reduce the binding update signaling cost and improve the network performance as long as a suitable threshold is chosen. The discussions on the sensitivity of tele-parameters are also given.展开更多
To relieve the negative effect brought by the intricate wireless network environment and unstable user behavior in layered mobile peer-to peer(P2P) streaming service, an evolved layered P2P (E-LP2P) data scheduling sc...To relieve the negative effect brought by the intricate wireless network environment and unstable user behavior in layered mobile peer-to peer(P2P) streaming service, an evolved layered P2P (E-LP2P) data scheduling scheme in the process of service delivery is introduced in this paper. The data in base layer is scheduled according to its importance in streaming play to guarantee the basic play of streaming. The data in enhancement layer is scheduled according to the characters of streaming data, including its position and amount in server peer set in a multiple tied way towards the data in enhancement layer. To cope with the layer jitter caused by the fluctuation of bandwidth, jitter prevent mechanism is used to adjust the highest layer dynamically during the process of data scheduling. Simulation results show that the E-LP2P can provide good quality of service(QoS) performance in terms of throughput, layer delivery ratio, server load and useless packet ratio.展开更多
In both wireless local area networks (WLAN) and mobile ad hoc networks (MANET), the IEEE 802.11e medium access control (MAC) protocol is proposed for an effective quality of service (QoS) solution. A number of studies...In both wireless local area networks (WLAN) and mobile ad hoc networks (MANET), the IEEE 802.11e medium access control (MAC) protocol is proposed for an effective quality of service (QoS) solution. A number of studies have been done to enhance the performance of 802.11e in MANET by independently adjusting contention window (CW) size of each access category (AC) in every node. However, without the cooperation between the high priority flows and lower priority flows, the QoS goal of high priority flows cannot achieve effectively. In this article, a fuzzy logic based cooperative MAC protocol (FLCMAC) is proposed to cooperate amongst network flows and dynamically adjust access probability of each low priority flow affecting the high priority flows to satisfy their QoS requirement. The simulation results indicate that compared to the enhanced distributed channel access (EDCA) scheme of 802.11e, the FLCMAC consistently excels, in terms of throughput and delay under moderate and heavy background traffic both in single-hop and multi-hop scenarios.展开更多
基金supported by the Natural Science Foundation of Jiangsu Province (BK2009469)the Fundamental Research Funds for the Central Universities (BUPT2009RC0120)the National Natural Science Foundation of China (60772110)
文摘By introducing a mobility anchor point (MAP), hierarchical mobile IPv6 (HMIPv6) reduces the binding update signaling cost associated with mobile IPv6, but there still exist deficiencies. For instance, a mobile node (MN) needs to orderly accomplish two binding updates with the MAP and home agent (HA) when the MN performs inter-MAP mobility. This results in a high signaling cost, thus affecting network performance. To reduce the inter-MAP binding update cost of idle MN in HMIPv6, an optimization scheme based on pointer forwarding with a threshold is proposed. The scheme can reduces the binding update cost of idle MN by using the binding update between MAP to replace several home binding updates. The signaling cost difference is derived by analyzing the cost of the basic scheme and the optimization scheme between two successive sessions. Simulation results show that, the optimization scheme can reduce the binding update signaling cost and improve the network performance as long as a suitable threshold is chosen. The discussions on the sensitivity of tele-parameters are also given.
基金supported by the National Natural Science Foundation of China (60902047)the Fundamental Research Funds for the Central Universities (BUPT 2009RC0120)
文摘To relieve the negative effect brought by the intricate wireless network environment and unstable user behavior in layered mobile peer-to peer(P2P) streaming service, an evolved layered P2P (E-LP2P) data scheduling scheme in the process of service delivery is introduced in this paper. The data in base layer is scheduled according to its importance in streaming play to guarantee the basic play of streaming. The data in enhancement layer is scheduled according to the characters of streaming data, including its position and amount in server peer set in a multiple tied way towards the data in enhancement layer. To cope with the layer jitter caused by the fluctuation of bandwidth, jitter prevent mechanism is used to adjust the highest layer dynamically during the process of data scheduling. Simulation results show that the E-LP2P can provide good quality of service(QoS) performance in terms of throughput, layer delivery ratio, server load and useless packet ratio.
基金the National Natural Science Foundation of China(60772109).
文摘In both wireless local area networks (WLAN) and mobile ad hoc networks (MANET), the IEEE 802.11e medium access control (MAC) protocol is proposed for an effective quality of service (QoS) solution. A number of studies have been done to enhance the performance of 802.11e in MANET by independently adjusting contention window (CW) size of each access category (AC) in every node. However, without the cooperation between the high priority flows and lower priority flows, the QoS goal of high priority flows cannot achieve effectively. In this article, a fuzzy logic based cooperative MAC protocol (FLCMAC) is proposed to cooperate amongst network flows and dynamically adjust access probability of each low priority flow affecting the high priority flows to satisfy their QoS requirement. The simulation results indicate that compared to the enhanced distributed channel access (EDCA) scheme of 802.11e, the FLCMAC consistently excels, in terms of throughput and delay under moderate and heavy background traffic both in single-hop and multi-hop scenarios.